Basic Turning



Particle boundary

Refers to the boundary along the particles within the structure.


Particle growth inhibitor

Prevents or limits the grain growth in the sintering operation.



This refers to a term given to the number of times the cut needs to be carried out.


Plasma electro-discharge

A process that uses electricity to break down the charged particles.


Plastic deformation

Plastic deformation is a term used to describe the deformation that remains permanent after release of the stress exerted on it.


PN edge type

A cutting edge configuration in which the axial rake angle is negative and the radial rake angle is positive. This type of configuration is not put into practical use as the cutting edge is not sharp and chip evacuation is poor.


Polycrystalline compacts (sintered super-hardened compacts)

Polycrystalline compacts is a term that refers to CBN and PCD tool grades. These tool grades are manufactured by adding metal or ceramic powders to powders of an ultra-hard cutting tool material like PCB and CBN. Once they have been added together the tool grade is sintered under high temperature and high-pressure conditions.



Rake angle

The rake angle is the angle between a line perpendicular to the machined surface and the rake face.



A process that is used to finish machine a pre-drilled hole.


Re-crystallization temperature

When in the solid state a temperature at which recrystallization takes place.


Removing scale

Removing the surface of a casting or a hot rolled work piece. Scale is a black substance due to the sand of a sand mould, or an oxidizing film.





Positioning accuracy

A term that refers to the accuracy of the position of the cutting edge when changed.


Positive land

The land of the cutting edge is not flat, it is given a slight angle to that makes it positive.



This term refers to the power needed to make machining possible.


ppm order

Parts per million.



A chemical process in which a solid substance is separated from a solution.


Pull stud

A stud that is screwed into back end of a BT shank holder. When the holder is inserted into the spindle this pull stub is gripped and pulled upwards thus securely locating the holder.


PVD-coated carbide

A carbide that has been coated using physical vapor deposition coating method.













Residual stress

When a body is not exerted to any outside force, the residual stress refers to the internal stresses that remain inside a material after it has been formed.


Retained austenite

Generally at ambient temperatures austenite is not found. However under certain cooling conditions, austenite can be retained in the grain structure.



A thin sectioned wall to support a mould.



The term rigidity refers to the ability of a material to withstand bending or twisting.


Roller bearing

A device that comprises of rollers that are

housed inside a bearing. It is used to

reduce the friction between 2 rotating